lkml.org 
[lkml]   [1996]   [May]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: CONFIG_RANDOM option for 1.99.2
Date
In article <Pine.OSF.3.91.960517093442.5381G-100000@namu23.gwdg.de>,
Martin.Dalecki <dalecki@namu23.Num.Math.Uni-Goettingen.de> wrote:
>
> No definitly false. Monte Carlo methods are based on *equally distributed*
> sequences. They are not based on *random* sequences. That's a subtile
> difference!
>

It is also a completely bogus assertion. The sequence 1, 2, 3, 4... ,
100, 1, 2... is equally distributed on the integers [1,100] but is
useless for MC. MC requires *uncorrelated* numbers. That is *not* a
subtle difference!

Equal distribution is not a necessity, however. It can easily be shown
that as long as the uncorrelated criterion is satisfied, a biased
random number source can be turned into an unbiased source with lower
production.

> And finally random.c is not as random as You may beleve. Start it on an
> otherwise not busy machine to see why! Yust do cat /dev/random and see
> the random numbers coming precisely after any keybord hit. This isn't
> acceptable for any number cruching, since those are mostly programms
> which are supposed to run in core and on otherwise idle machines.

random.c is just fine and random, but it doesn't have unlimited output
without special hardware. That is why there is /dev/urandom.

-hpa




\
 
 \ /
  Last update: 2005-03-22 13:37    [W:0.133 / U:0.584 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site